html {
    background: #ffc600;
}

.inbox {
    width: 400px;
    margin: 50px auto;
    background: white;
    border-radius: 5px;
    box-shadow: 10px 10px 0 rgba(0, 0, 0, 0.1);
}

.item {
    display: flex;
    align-items: center;
    border-bottom: 1px solid #F1F1F1;
}

.item:last-child {
    border-bottom: 0;
}

input[type='checkbox'] {
    margin: 20px;
    outline: 0;
}

p {
    margin: 0;
    padding: 20px;
    border-left: 1px solid #D1E2FF;
    display: flex;
    flex: 1;
}

input:checked+p {
    background: #F9F9F9;
    text-decoration: line-through;
    border-radius: 0 5px 5px 0;
}